Ok, so….

I’ve gotten some good info from the forum, and wanted to join and contribute! I’ve owned my runner for 11 years, she has 220,000+ miles, and she’s just getting broke in

I had a gas leak for the past few years that eventually got so bad I had to park the thing for over a year. I took it to a mechanics, and $850 later….. the leak was just as bad if not worse. They changed out a few injectors… did the o-rings SEVERAL times… even switched out a fuel rail (I have no idea why) but nothing worked and I was fed up. I decided to tackle the problem myself, and learned a few things that some may already know, but for those who don’t it will be good info. Below is what I did, and a few tricks I learned:

I went through and replaced ALL the O-rings from the injector insulator ring all the way up to the fuel rail ring. I figured while I was in there I might as well do them all! The hole where the injector insulator plugged into the engine was pretty grimy so I cleaned all the holes with a toothbrush and some gas before installing the insulator.

The first important tip I can give is to buy the o-rings and gaskets FROM THE DEALERSHIP! I know it’s a rip off, and I know it sounds silly, but I compared the dealership rings to aftermarket rings and there really is a difference! It seems the factory rings are made from a much higher quality rubber and they seem to fit better.

In the repair manual, and a few other places, I read that if an injector is installed wrong (sideways) it should be pulled out and a new o-ring used to reinstall. I think WAY to much emphasis was put on the possibility of installing it wrong! I clamped the fuel rail gently in my vice and made sure it was plumb and level. I then put a little (very little) Vaseline on each o-ring (to ease installation) and carefully inserted the injectors into the fuel rail. Piece of cake! Then the whole assembly gets dropped into the manifold, with a little Vaseline on the tips of the injectors. Once installed, they all rotated smoothly, just as specified

When I had all the injectors out, I tested them one by one for competency. First I applied 12 volts to make sure there was a good strong “click” then I pressurized them with my compressor at 35 pounds. This test instantly revealed a leak on the side of one injector, and I replaced it.

Before I dropped the intake manifold back down onto the engine, I plugged all holes (pressure regulator, cold start injector line) to seal the system, then jumped the Fp and B+ ports to pressurize it with fuel. I waited for the pump to run up and fill the lines, then checked carefully for any leaks. Not a drop I highly recommend doing this pressure test before you re-install the manifold to make sure everything is good. This test showed me i had a bad pressure damper.

Hope this helps! Feel free to ask questions if i don't make any sense....

 

Appreciate the information.

Out of curiousity, what year, model and engine do you have?

 

It's the 3.0 EFI on a 91 SR5, on my avatar..... Aint she a bute?

 

Good work!

 

Thanks for the post,

Good info to have, a leaking injector body was most likely your culprit?

Mike

 

atta boy. i chased almost the exact same thing as you for a while in almost the exact same rig lol. wound up being the same couple o rings and a fuel pressure regulator and she was tip top. theres a certain pride that comes from not taking it to the stealership for work. but i agree with the parts oem is usually the best way to go

 

fuel leak for a few years? Since it was up front was it a really strong smell or could you see it dripping when the car was running?

 

Once I researched and gained an understanding of the fuel system and knew where to look, I was able to see the injector insulators were wet with fuel. Actually….. several of them were! It ended up being a leaking injector body, and the o-rings installed by the mechanic were garbage; all but one injector was leaking from somewhere. The pressure damper also dripped a little, so I replaced it.

BTW…… the aftermarket damper I got from checker auto was garbage!!! It broke while I was installing it. I ended up paying the extra bucks and got one from the dealership. MUCH higher quality…. By a factor of ten at least!

 

just another 5 cents worth of knowledge- hylomar. If you're going to be putting it together and taking it apart... hylomar works better than any FIPG sealant I've seen. It works well if you're not going to be taking it apart too. Did I say that already?
I put hylomar on my injector seals and intake gaskets on my 91 and they haven't failed in over 3000 miles in spite of me disassembling and re-assembling things.
Rolls Royce uses it on their turbine (read- jet engines) so it must not be that bad.

And it's high in protein and fiber for your little ones.